Major Wilhelm Trapp, nicknamed Papa Trapp by his subordinates  (Nitzow, 4 September 1889 – executed 18 December 1948, Siedlce) was a career policeman who commanded the Reserve Police Battalion 101 formation of Nazi Germany uniformed police force known as Order Police (Ordnungspolizei).
A World War I veteran and recipient of the Iron Cross First Class, an "old Party fighter", who joined the Nazi Party in December 1932, Trapp served in occupied Poland during World War II, subsequently leading his battalion of nearly 500 middle-aged men on genocidal missions against the Polish Jews.
He was captured after the war by the Allies and handed over to the British authorities. After investigation by the Polish Military Mission he was extradited to Poland in 1946, and charged with war crimes and crimes against humanity. Trapp was found guilty and sentenced to death by the Siedlce District Court on 6 July 1948, and executed on 18 December 1948.
The killing of 1,500 of the 1,800 Jews from Józefów Ghetto southeast of Warsaw on 13 July 1942  was performed by the First Company, and, mostly, by the three platoons of the Second Company. Trapp gave his commanders their respective assignments before the operation.
The men were explicitly ordered to shoot anyone trying to escape. The remaining men were to round up the Jews and take them to the marketplace. Those too sick or frail to walk to the marketplace, as well as infants and anyone offering resistance or attempting to hide, were to be shot on the spot.
The battalion left for Biłgoraj at 9 pm. Trapp later remarked to his driver: "If this Jewish business is ever avenged on earth, then have mercy on us Germans ... But orders are orders", he said.
- Browning (2017), p. 7.
- Browning (2017), p. 64.
- Browning (2017), pp. 69-76.
- Trials (Sygn. GK 284), Trapp Gustaw: File SOSBP 45. Protocols. Siedlce (Poland) Sąd Okręgowy: Instytut Pamięci Narodowej; Komisja Ścigania Zbrodni przeciwko Narodowi Polskiemu, ul. Towarowa 28, Warsaw, Poland. PDF file from ushmm.org; retrieved 3 December 2014.
- Dokumentationszentrum für Kriegsverbrecherprozesse (ICWC): Polen Philipps-Universität Marburg - ICWC.
- Struan Robertson. "Hamburg Police Battalions during the Second World War". Archived from the original (Internet Archive) on 22 February 2008. Retrieved 24 September 2009.
- Browning (2017), pp. 7-8.
- Browning (2017), p. 81.
- Robert Kuwalek, Chris Webb (2007). "Jozefow". Holocaust Research Project.org. Holocaust Education & Archive Research Team. Retrieved 17 June 2014.
- Marta Kubiszyn (2014). "Józefów. Lata okupacji". Virtual Shtetl.org. Muzeum Historii Żydów Polskich. Retrieved 17 June 2014.
- Browning (2017), p. 102.
- Browning (2017), p. 83.
- Browning, Christopher R. (2017) . Ordinary Men: Reserve Police Battalion 101 and the Final Solution in Poland (revised ed.). Harper Perennial. ISBN 9780062303028. See also Penguin Books edition.
- Goldhagen, Daniel J. (1997). Hitler's Willing Executioners: Ordinary Germans and the Holocaust. Abacus. ISBN 978-0349107868.